code: def test_with_empty_content():
      message = ChatMessage.from_user("")
      assert message.content == ""
  
file_path: haystack/test/dataclasses/test_chat_message.py
imports: import pytest
  from transformers import AutoTokenizer
  from haystack.dataclasses import ChatMessage, ChatRole
label_desc: Use image node_id 4 for calling a global function with example usage: test_with_empty_content() without return types